UK Defence Forum

Job jobbed

SW1 wrote: ↑25 Feb 2023, 09:06 Reads a lot like mitigations have been put in place rather than fixes to causes.

Does it?

mr.fred wrote: ↑25 Feb 2023, 14:24

SW1 wrote: ↑25 Feb 2023, 09:06 Reads a lot like mitigations have been put in place rather than fixes to causes.

Does it?

Yes read like in service fixes to keep the customer happy. Rather than production fixes

Little J wrote: ↑25 Feb 2023, 13:24 Job jobbed

Sometimes the simple things are the best but one has to guess that more has been done it would mad to think we were going to bin a hole program for the want of some better headsets and cushions

SW1 wrote: ↑25 Feb 2023, 15:06 Yes read like in service fixes to keep the customer happy. Rather than production fixes

It does sound a bit like that's the angle the Times is going with. I'd only read the Guardian piece when I posted

The ear defenders bit, we know that all AFVs need them and we know that the Army already had problems with the in service ones. It took Ajax to bring it to light, but it wasn't unique to Ajax. The noise fixes are fixes, even if that isn't something that works as a headline.

With the vibration, whatever they did (compare the language between the two articles) was enough to get it past the initial trials focussing on that aspect. Given that the vehicle is already in production and more than 100 have been built, any fix will be a retrofit to those vehicles already produced. Presumably that will also be incorporated into all remaining production, so what's the problem?

Tempest414 wrote: ↑25 Feb 2023, 16:29 Sometimes the simple things are the best but one has to guess that more has been done it would mad to think we were going to bin a hole program for the want of some better headsets and cushions

Mad? yes.
What many people have been calling for? Also yes

mr.fred wrote: ↑25 Feb 2023, 16:31

SW1 wrote: ↑25 Feb 2023, 15:06 Yes read like in service fixes to keep the customer happy. Rather than production fixes

It does sound a bit like that's the angle the Times is going with. I'd only read the Guardian piece when I posted

The ear defenders bit, we know that all AFVs need them and we know that the Army already had problems with the in service ones. It took Ajax to bring it to light, but it wasn't unique to Ajax. The noise fixes are fixes, even if that isn't something that works as a headline.

With the vibration, whatever they did (compare the language between the two articles) was enough to get it past the initial trials focussing on that aspect. Given that the vehicle is already in production and more than 100 have been built, any fix will be a retrofit to those vehicles already produced. Presumably that will also be incorporated into all remaining production, so what's the problem?

If it’s a problem or not I don’t know. But it sounds like there has been mitigation to ensure injury to soldiers can be claimed as within H&S limits which is fair enough. But the question remains if vibration and resonance are remaining within the hull then what does that do to thru life effect on installed equipment or future equipment and the ensuing maintenance bill that’s the problem.

SW1 wrote: ↑25 Feb 2023, 16:40 But the question remains if vibration and resonance are remaining within the hull

It's a 40 tonne tracked vehicle, there will be vibration and resonance in the hull. No tracked AFV is without it.

SW1 wrote: ↑25 Feb 2023, 16:40 then what does that do to thru life effect on installed equipment or future equipment and the ensuing maintenance bill that’s the problem.

The equipment will have shorter lives that they'd otherwise have. Determining if the life of the equipment is suitable for the vehicle in service is what the reliability growth trials, which the vehicle is now embarking on, are for.

SW1 wrote: ↑25 Feb 2023, 16:40 But it sounds like there has been mitigation to ensure injury to soldiers can be claimed as within H&S limits which is fair enough.

The H&S vibration limits ought to ensure that there are no injuries.

SW1 wrote: ↑25 Feb 2023, 16:40 If it’s a problem or not I don’t know. But it sounds like there has been mitigation to ensure injury to soldiers can be claimed as within H&S limits which is fair enough. But the question remains if vibration and resonance are remaining within the hull then what does that do to thru life effect on installed equipment or future equipment and the ensuing maintenance bill that’s the problem.

Well that's what Reliability Growth Testing and Qualification of sub-systems. Otherwise, what's the point of either of them?

RunningStrong wrote: ↑25 Feb 2023, 18:07

SW1 wrote: ↑25 Feb 2023, 16:40 If it’s a problem or not I don’t know. But it sounds like there has been mitigation to ensure injury to soldiers can be claimed as within H&S limits which is fair enough. But the question remains if vibration and resonance are remaining within the hull then what does that do to thru life effect on installed equipment or future equipment and the ensuing maintenance bill that’s the problem.

Well that's what Reliability Growth Testing and Qualification of sub-systems. Otherwise, what's the point of either of them?

Well it is but we seem to have a number of senior officers and ministers claiming all is well already.

mr.fred wrote: ↑25 Feb 2023, 17:23

SW1 wrote: ↑25 Feb 2023, 16:40 But the question remains if vibration and resonance are remaining within the hull

It's a 40 tonne tracked vehicle, there will be vibration and resonance in the hull. No tracked AFV is without it.

SW1 wrote: ↑25 Feb 2023, 16:40 then what does that do to thru life effect on installed equipment or future equipment and the ensuing maintenance bill that’s the problem.

The equipment will have shorter lives that they'd otherwise have. Determining if the life of the equipment is suitable for the vehicle in service is what the reliability growth trials, which the vehicle is now embarking on, are for.

SW1 wrote: ↑25 Feb 2023, 16:40 But it sounds like there has been mitigation to ensure injury to soldiers can be claimed as within H&S limits which is fair enough.

The H&S vibration limits ought to ensure that there are no injuries.

Of course there will still be vibrations the question is, what have they done/changed to reduce the excessive levels it has had up to now if anything.

SW1 wrote: ↑25 Feb 2023, 18:30

RunningStrong wrote: ↑25 Feb 2023, 18:07

SW1 wrote: ↑25 Feb 2023, 16:40 If it’s a problem or not I don’t know. But it sounds like there has been mitigation to ensure injury to soldiers can be claimed as within H&S limits which is fair enough. But the question remains if vibration and resonance are remaining within the hull then what does that do to thru life effect on installed equipment or future equipment and the ensuing maintenance bill that’s the problem.

Well that's what Reliability Growth Testing and Qualification of sub-systems. Otherwise, what's the point of either of them?

Well it is but we seem to have a number of senior officers and ministers claiming all is well already.

Well yeah because the hardware has been running around in AJAX vehicles for 5 years now...

RunningStrong wrote: ↑25 Feb 2023, 19:10

SW1 wrote: ↑25 Feb 2023, 18:30

RunningStrong wrote: ↑25 Feb 2023, 18:07

SW1 wrote: ↑25 Feb 2023, 16:40 If it’s a problem or not I don’t know. But it sounds like there has been mitigation to ensure injury to soldiers can be claimed as within H&S limits which is fair enough. But the question remains if vibration and resonance are remaining within the hull then what does that do to thru life effect on installed equipment or future equipment and the ensuing maintenance bill that’s the problem.

Well that's what Reliability Growth Testing and Qualification of sub-systems. Otherwise, what's the point of either of them?

Well it is but we seem to have a number of senior officers and ministers claiming all is well already.

Well yeah because the hardware has been running around in AJAX vehicles for 5 years now...

If AJAX was OK all along what was the point of all the hullabaloo then?

tomuk wrote: ↑25 Feb 2023, 21:30 If AJAX was OK all along what was the point of all the hullabaloo then?

Politics, partly. AJAX is held to standards that far exceed any of the legacy platforms in the British Army (and MOD is increasingly held to the same standards as civilian employers), and also the army insists on mandating PPE that was inadequate before and is increasingly so to today.

Since vibration induced injuries can also come through the floor perhaps they put the padding on the floor as well ,I have included a few international articles on vibration people here can work out if all of the transmission points of vibration to feet and hands have been protected
https://view.officeapps.live.com/op/vie ... BROWSELINK
https://pubmed.ncbi.nlm.nih.gov/14594190/
https://occup-med.biomedcentral.com/art ... 20-00269-w

Zeno wrote: ↑26 Feb 2023, 05:45 Since vibration induced injuries can also come through the floor perhaps they put the padding on the floor as well ,I have included a few international articles on vibration people here can work out if all of the transmission points of vibration to feet and hands have been protected

Foot vibrations have been solved with some comfy sheepskin slippers.

Said the GDLS chassis for the new US Army Mobile Protected Firepower/light tank was based on the Ajax, one of the major changes GDLS made was an advanced suspension, the suspension changed from the Ajax torsion bar to hydro-pneumatic.

The competition for the MPF contract was between GDLS and BAE Inc, with an updated M8 Buford, prototype trials were held with both companies vehicles, GDLS mentioned the positive feedback on the new suspension during the soldier vehicle assessment phase.

From above GD knew about the rough ride of the Ajax chassis more than a few years ago.

NickC wrote: ↑26 Feb 2023, 10:55 aid the GDLS chassis for the new US Army Mobile Protected Firepower/light tank was based on the Ajax,

A frequently stated falsehood.

GD USA built a concept vehicle using parts from the spares bin including Ajax, to see if there was any interest from the US army. There was interest so a new vehicle was designed with no Ajax parts or design. The resulting vehicle has zero to do with Ajax.

The lesson the UK has yet to absorb is that basing a new vehicle on an old chassis is a very bad idea. If the MoD wanted a low cost, quickly available solution, it should have chosen CV90 which was then (and now) in full production and service use.

If the MoD wanted a brand new vehicle, it should have asked for a new one to be designed. But not by GD UK, who didn't have a clue but Bae or KMV or Rheinmetal.

Zeno wrote: ↑26 Feb 2023, 05:45 Since vibration induced injuries can also come through the floor perhaps they put the padding on the floor as well

It's also possible that it was resonances rather than source vibration that were the problem, although the reports implicating the running gear kind of indicates against that.
Or the foot rests were already sufficiently isolated.
Or the vibration wasn't in the frequency range that affects lower limbs.

Quite a few AFVs have isolated or padded floors or footrests, though the latter tends to be for mineblast protection as much as anything else.

NickC wrote: ↑26 Feb 2023, 10:55 From above GD knew about the rough ride of the Ajax chassis more than a few years ago.

There are a few reasons to choose hydropneumatic over torsion bar, so I wouldn't take it as read.

Ron5 wrote: ↑26 Feb 2023, 13:33, it should have chosen CV90 which was then (and now) in full production and service use.

Oh yeah the famous CV90 mk4 that was unveiled in... 2021. Not in production, not in service.

Ron5 wrote: ↑26 Feb 2023, 13:33
If the MoD wanted a brand new vehicle, it should have asked for a new one to be designed. But not by GD UK, who didn't have a clue but Bae or KMV or Rheinmetal.

I have to wonder. Ajax is a new gun, turret, optronics, electrical architecture and a euro standard power pack and we’re compromising all that for the sake of the base platform? How expensive would it really be to fire up CAD/CAM and design a new chassis from scratch. Hydragas suspension based on ch2. RBSL would do it for them.

SD67 wrote: ↑26 Feb 2023, 22:07

Ron5 wrote: ↑26 Feb 2023, 13:33
If the MoD wanted a brand new vehicle, it should have asked for a new one to be designed. But not by GD UK, who didn't have a clue but Bae or KMV or Rheinmetal.

I have to wonder. Ajax is a new gun, turret, optronics, electrical architecture and a euro standard power pack and we’re compromising all that for the sake of the base platform? How expensive would it really be to fire up CAD/CAM and design a new chassis from scratch. Hydragas suspension based on ch2. RBSL would do it for them.

Or you could have built new warrior hulls and put the reconnaissance equipment in them and made the warrior ifv upgrade more straight fwd.

SD67 wrote: ↑26 Feb 2023, 22:07

Ron5 wrote: ↑26 Feb 2023, 13:33
If the MoD wanted a brand new vehicle, it should have asked for a new one to be designed. But not by GD UK, who didn't have a clue but Bae or KMV or Rheinmetal.

I have to wonder. Ajax is a new gun, turret, optronics, electrical architecture and a euro standard power pack and we’re compromising all that for the sake of the base platform? How expensive would it really be to fire up CAD/CAM and design a new chassis from scratch. Hydragas suspension based on ch2. RBSL would do it for them.

Yes but didn't the original procurement require it was an existing platform based on the believe that it would be cheaper and easier than starting from scratch.

Just like Nimrod MR4A, an upgrade despite everything but the fuselage barrel being new, because an upgrade could be justified but not new build.

mr.fred wrote: ↑26 Feb 2023, 14:07

NickC wrote: ↑26 Feb 2023, 10:55 From above GD knew about the rough ride of the Ajax chassis more than a few years ago.

There are a few reasons to choose hydropneumatic over torsion bar, so I wouldn't take it as read.

The Challenger hydro-pneumatic suspension said to have provided years of outstanding cross-country performance through the long suspension arm travel and controlled bump and rebound behaviour offered, surely with that successful experience with hydro-pneumatic suspension why did Army not make it a requirement for the Ajax chassis?

The whole procurement process was very odd.
Why did the mod commit to signing a production contract before GD had demonstrated that their initial test vehicles met the armies requirements?
Same with awarding LM the Warrior LEP contract without ever demonstrating that they knew how to build a turret that met the armies requirements, then letting them to drag it out for at least 10 years before they could successfully complete trials before cancelling.
I don't think they actually got a production contract for that one, but LM still received huge amounts of money to develop their own turret when BAE already have their own turret that had completed military certification.
I can understand taking risks when it comes to building ships and submarines etc, but for land vehicles and aircraft, the test vehicles always come before awarding production contracts, usually as part of a competition and would have identified and avoided these issues over 10 years ago.